for some reason my d-pillar speakers and my factory subwoofer stopped working. i replaced the d pillar speakers and after about 6mths they quit playing. thinking they were blown i just bought another pair of bullet tweeter for like 20 bucks from a friend. those didnt work either so i tested both sets of speakers on the house stereo and they both played pretty well. then i thought to check my factory sub connection to se if they were good(factory sub has been disconnected before any of this happened)but they were not powering the tweeters either. i checked fuses under the hood and inside by the dash and there was a fuse blown but had nothing to do with the audio, and after replacing it , had no effect. am i missing something. could one of those huge black fuses be bad. can i just pull them out . how do i check them. ANY feedback would be greatly appreciated.